1. Field of the Invention
The present invention relates to a liquid heating apparatus of the pulse combustion type, and more particularly to a liquid heating apparatus which includes means for preventing the pulse combustion burner from its careless activation in a condition where there is not any liquid in the vessel.
2. Description of the Prior Art
In general, a conventional liquid heating apparatus of the pulse combustion type includes a liquid vessel arranged to store an amount of liquid such as cooking oil or other fluid medium to be heated, a pulse combustion burner mounted to the vessel and having a combustion chamber secured at its inlet end to a side wall of the vessel and immersed in the liquid, and a tailpipe connected at one end thereof to an exhaust port of the combustion chamber in such a manner that the great part of the tailpipe is immersed in the liquid. The conventional liquid heating apparatus, however, does not act to automatically prevent the pulse combustion burner from its careless activation in a condition where there is not any liquid in the vessel. It is, therefore, needed in use to confirm as to whether a sufficient amount of liquid is stored in the vessel or not prior to activation of the burner. If the burner is carelessly activated without any liquid in the vessel, the component parts of the heating apparatus will be damaged due to overheat of the burner.
To avoid such careless activation of the burner, a liquid level detection switch may be provided within the vessel to maintain the burner in its deactivated condition when it has been detected that the level of stored liquid in the vessel is below a predetermined minimum level. The provision of the detection switch, however, results in an increase of manufacturing cost of the heating apparatus.